


First One, Then The Other

by Mrs_SimonTam_PHD



Category: Supernatural
Genre: Growing Up, M/M, Neighbors AU, No Supernatural AU, Sibling Incest, background sastiel, sex mention
Language: English
Status: Completed
Published: 2018-12-04
Updated: 2018-12-04
Packaged: 2019-09-07 13:22:17
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,770
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16854751
Author URL: https://archiveofourown.org/users/Mrs_SimonTam_PHD/pseuds/Mrs_SimonTam_PHD
Summary: How Dean Winchester fell for Michael and Lucifer Milton





	First One, Then The Other

**Author's Note:**

> Originally posted on tumblr. 
> 
> For the Poly Triad Square for the SPN Poly Bingo Card

How rare is it that a man falls for both brothers at the same time?

Dean Winchester feels like typically you fall in love with one, than the other, and when you fall for Brother Number 2, your feelings for Brother Number 1 dissipate.

How wrong he was. At least, for him.

And was it so wrong that he was loved and protected by these men? That they shared a bond that was once the cultural norm and is now a taboo? He didn’t think so. It’s not like two men can make a child together.

Michael and Lucifer Milton are brothers, lovers, and confidants. Lucifer and Dean were the same age and when Dean, his little brother Sam, and their dad moved into the house across the street from Chuck Milton and his five sons when Dean was fifteen, Lucifer was the first brother Dean saw. Sam had gravitated towards Castiel almost immediately, and Dean and Lucifer butted heads at first. Dean had always made himself out to be a tough guy and usually, a fist thrown here and there was all that was needed to assert his authority as such when he moved into a new town. Lucifer wasn’t so easily dissuaded by Dean, and the two were constantly in fights, both at home and at school. They just made sure that their fights were out of line of sight of teachers, snitches, their younger brothers, and their respective fathers. Michael was away at college and therefore the two didn’t need to worry about him.

Everything then came to a head about three months after the Winchesters moved to the area. It was lunch time at the small school, and Dean had texted Sam to make sure that he had enough to eat at the middle school down the road. He knew that Sam probably would- Castiel had taken to packing a little extra for his new friend. Dean was glad Sam had a friend that he could nerd out with, the eleven year old tended to be too serious for Dean’s liking, and Sam was often picked on. Castiel may be a scrawny kid, but he could sure pack a punch.

Lucifer had made a comment about Dean’s mom- wondering why she wasn’t there, or something like that. An insinuation that she had ran off because she didn’t want Dean. Dean didn’t remember. He just remembered seeing red and launching himself across the cafeteria at the blond boy, fists flying.

Lucifer had given it back as good as he got and it took four of the school security guards to pry the boys away from each other and haul them off to the principal’s office.

Both boys were suspended for a week for fighting in school. The principal was a bit more sympathetic to Dean- possibly because he was the new kid, possibly because Lucifer instigated it, something- but she suspended them for the same length of time. The nurse cleaned them both up while the principal called their fathers.

John Winchester had arrived at the same time as Chuck Milton, and the two fathers were talking amicably with each other. As single fathers, they felt they had to stick together, and they had become good friends as well as their youngest sons.

The car ride home from school was silent. John waited until they were home before sitting Dean down and asking what happened. Dean told him what had happened and John had sighed.

As it turned out, the Miltons’ mother had died in a car accident about two years ago, which was when Lucifer’s behavior switched to what he was now. Lucifer blamed himself, as she was on her way to pick him and their older brother up from the library. Dean felt sick, knowing what it was like to lose his mother. Sam didn’t know Mary and Dean could barely talk about her. But that didn’t give Lucifer the right to insult Mary, to which John agreed.

John wasn’t happy that Dean was fighting Lucifer, but he understood why Dean had snapped that day. He did tell Dean that while he won’t ground him, there’ll be a punishment for both him and Lucifer that Chuck and he will decide. Dean had shrugged it off. John was strict, but he was fair, and he had the feeling Chuck would be the same.

Boy, was he wrong.

The boys’ joint punishment was watching over Sam and Castiel while catching up on their homework after school. Dean found this punishment more ridiculous than Lucifer, as he had pointed out to John that Sam had known how to stay on his own by the time he was nine. John had agreed, but also reminded Dean that Castiel wasn’t, and with both boys spending almost every waking moment together, it was better to have two sets of eyes on them than one. Dean couldn’t argue with that logic.

The first two days were the most stressful. Dean had to consistently prevent Lucifer from copying his math homework; Lucifer had complained about how much food Dean ate while they watched the two eleven year olds.

The first breakthrough came when Dean got tired of trying to do homework in silence other than snarking at Lucifer or Sam and Castiel all of a sudden babbling at each other in some kind of tongues for two days. He had pulled up his Walkman that he had repaired on a whim and attached it to the aux cable of the Shurelys’ boombox. The Eagles had started playing and Lucifer seemed to perk up as “Hotel California” wafted through the air.

Sam and Castiel seemed to give each other identical looks of oh God while Lucifer quizzed Dean about the band, both of them impressed with the others’ knowledge of classic rock in general.

The second breakthrough came when Sam and Castiel begged their fathers for a sleep over while Dean and Lucifer were suspended. Neither Dean nor Lucifer trusted their little brothers’ motives for this sleepover, especially when they were asking for a night that Dean knew was going to be his father travelling to a classic car show.

They especially distrusted their fathers who had talked it over and informed the two boys that they could have the sleepover, because Dean and Lucifer would be there as well. Dean’s not sure if he had ever wanted to commit patricide more than then.

But another pleasant shock had come in when Lucifer offered to help Dean build his computer, having built his own about a year before.

And it was then that they actually talked, while Sam and Castiel were curled up on the couch watching a scary movie that neither Dean nor Lucifer paid attention to. They talked about losing their mothers, talking about the consistent moving. They talked about how hard it was having younger brothers. Dean winced when he realized that Gabriel and Balthazar were actually twins who had a mischievous streak about a mile wide. They learned that beyond an avid love for building things and classic rock, they had a lot in common. The ‘tough guy’ was actually a facade. Their favorite foods were the same, although Lucifer was a ‘cake’ man. They liked to cook. They sucked with traditional schoolwork when it came to math, although they instinctively knew what to do with things that required a bunch of math. Dean’s best subject was history, due to Sam loving Dean reading him books about history; Lucifer’s was English and creative writing. They both loved wrestling.

They may’ve not considered themselves friends by this point, but they had each other’s respect.

The friendship came at Christmas, when Michael came home from college. They didn’t see much of him, the oldest Milton brother having slept through a majority of his Christmas break. Not that anyone could blame him, as Castiel had mentioned his oldest brother took eighteen hour credits and was also involved in a couple of different organizations and teams.

It was clear that Lucifer worshipped his older brother, but Michael didn’t have much time to spend with his brother. It stung Lucifer, so Dean did what he could to cheer him up. He had met Michael when the Miltons and the Winchesters combined their families smack in between Christmas and New Years’ to do their combined Christmas celebration. Michael hadn’t gotten gifts for the Winchesters, and he had apologized profusely for it, saying he didn’t want to offend them or anything. John had waved him off, gesturing towards where Castiel and Sam were exchanging books and speaking in tongues. Dean’s heart had swelled at the sight and when he caught Lucifer’s eye, he knew Lucifer was feeling the same way.

The two had exchanged gifts themselves. Dean got Lucifer a Walkman, modified to have a longer battery life and hold a few more songs. It had taken Dean weeks of staying up extremely late to make it, but it was worth it to see Lucifer’s face. Lucifer had given Dean a few vinyls for his record player that Dean had in his room and Dean was overjoyed by the gift.

It wasn’t long after Christmas that the two were joined at the hip. Teachers breathed a sigh of relief as they noted both boys were amicable towards each other now, best friends in fact. Some had started a betting pool to see if Dean and Lucifer would become an item.

Those teachers paid up when they noticed Lucifer and Dean holding hands in the hallway when the boys were seventeen and seniors in high school.

It had been a natural progression, if Dean and Lucifer were honest with themselves, to becoming boyfriends. They still had their fights, as neither Lucifer nor Dean were any good at talking about their feelings, but they knew how to work things out. More often than not, they were holding hands, stealing kisses in the hallway, texting each other during class or passing notes. Chuck and John were actually encouraged by this, and they had the feeling that Sam and Castiel weren’t far behind their elder brothers.

It was a surprise to Dean, therefore, as “in love” with Lucifer (they hadn’t said the words even after six months of dating) as he was when that Christmas Michael came home and Dean was struck by the sudden urge to walk up to Michael and kiss him like he’d kiss Lucifer. What was wrong with him? Especially when his dreams started manifesting Lucifer pressing up behind Dean and kissing Michael with the same ferocity that Dean had.

What was wrong with him?

He hoped that it’d go away when Michael went back to college. No such luck. If anything, the dreams got worse. Imagining both of them taking him apart…it drove Dean insane. And he and Lucifer hadn’t even fucked yet! Not from lack of wanting to- it was just harder when your brothers are nosy.

Lucifer had noticed something was off, and Dean waited until spring to inform Lucifer, looking ashamed.

Lucifer then confessed that he had been in love with Michael since he was Castiel’s and Sam’s age, and that Michael going to college so far away from home felt like a betrayal. He loved Dean, he assured him (and that sent a trill through Dean), but he also loved Michael.

And with that, the two hatched a plot to bring Michael into their fold after Michael’s graduation from college and Dean and Lucifer’s graduation from high school.

Not that the eldest Milton brother needed much convincing.

Michael had quickly established himself as the absolute head of their trio. Dean and Lucifer consistently challenged his authority, often with twinkles in their eye and laughter.

It was to Michael that Dean lost his virginity to, Lucifer holding his hands tight as Michael pressed into him and praising him to high heavens at how good he was taking Michael. Michael was tender, gentle, and it made Dean ache for days to come from both pleasure and love.

Lucifer got accepted at Michael’s alma mater, which worked as Michael was going to law school at the same college. Dean opted for a tech school nearby so the three could rent an apartment together. “Saving costs,” they informed their fathers. Neither John nor Chuck had an issue with it and agreed to it.

The three settled into a routine fairly quickly. Dean was in automotive repair and worked at a garage to help pay the bills; Lucifer was studying to become a police officer and worked at the local gun store to help; Michael attend his classes at night and worked as a paralegal during the day. The weekends, once Lucifer and Dean were home from work, was their time to be lovers. Dean quickly learned that he much preferred to submit to the two brothers, a fact that Lucifer and Michael delighted in exploiting. While Lucifer vastly preferred bottoming, he definitely was a Top and it was always enjoyable to watch Lucifer attempt to assert his authority over Michael whenever they fucked and were leaving Dean to recover and regain his senses.

Whenever they went home, Lucifer and Dean were the only ones who were all touchy feely. As predicted, Sam and Castiel ended up together and were talking about California for school and living.

It took Dean two years to complete his program and he was now a full time employee at the garage where he had been working for two years. He’d come home, covered in engine grease and always had to resist the urge to dirty Michael’s suit.

Another year later, and Michael was taking the bar exam, having graduated from law school. Lucifer and Dean did everything in their power to not let Michael get overly stressed about his results and assuring him that he would be fine. Michael ended up being one of those lucky bastards that passed the bar on the first try, and accepted a position as an associate at the law firm he was a paralegal at for so long, specializing in taxes.

Lucifer graduated a year afterwards and entered the police academy, becoming a police officer. Out of the three, he worked the longest hours and had the worst job. Dean remembered how he and Michael had to comfort their lover after Lucifer came home the first time he had to deliver the news of someone’s death to their doorstep.

They supported their younger brothers. Gabriel and Balthazar ended up opening their own bakery/candy store; Sam and Castiel were now living in California and talking of marriage after college. Castiel was studying religion and philosophy, wanting to write books on the subject. Sam was following in Michael’s footsteps of law school.

All in all, Lucifer, Dean, and Michael were very happy. When Lucifer and Dean officially tied the knot, they bought Michael his own wedding band and Michael’s “best man” speech was full of hidden jokes, innuendos, and hints of the three of them fucking around with each other that both Dean and Lucifer had trouble keeping straight faces during it. Michael did have a sly, dry mischievous side, after all, and that proved it.

Michael was content to play off the eternal bachelor, stating he was married to his work and besides, between Lucifer and Dean, Sam and Castiel, Balthazar and Crowley, and Gabriel and Kali, there were enough relationships. “One of us men has to remain single for the ultimate spoiling of nieces and nephews,” he joked.

No one questioned it.

Lucifer and Dean would tease their brother/husband about it, and Michael endured it good naturedly, loving his brother husbands for it. He wore his wedding band except when they had company or went home for the holidays. Michael, however, did express his outright indignation when it was discovered that Sam and Castiel had eloped in Las Vegas right before they graduated with their Masters’ degrees several years later. Sam and Castiel had pointed out that they had technically been married under common law and this was just the formality. Dean’s just glad that his baby brother didn’t get married by an Elvis impersonator.

There were fights. There were always fights between couples, and a triad was no different. Lucifer’s long hours were often a point of contention; Michael’s penchant for not apologizing put him on the couch more often than the oldest could say; and Dean’s tendency to snap and fight instead of talk when he’s upset caused a lot of hurt feelings. They always managed to work everything out somehow.

And that’s how Dean, Lucifer, and Michael liked it.

**Author's Note:**

> Tumblr: @lucibae-is-dancing-in-hell
> 
> Comments and Kudos are Shiny!!


End file.
